1. Field of the Invention
The present invention relates to an image creation technology executed by a computer, especially, to an image creation technology performed by using a color palette.
2. Description of the Related Art
Various technologies are developed as a technology to output an image to a television receiver, a monitor receiver or a CRT display device in a home video game, a personal computer device, or a graphic computer device, etc. There is a technology, which uses a color palette, among them.
The color palette is one kind of tables created by allocating a plurality of different codes to each of color informations which are information relating to different kinds of colors among colors displayed on a display device. An image data of a target image which becomes a display target in case of using a color palette is created as a set of a position information and a code configured by assigning the above-mentioned code, which becomes a pair with the color to be displayed to a pixel, to each position information corresponding to a position in the target image. And, data for image display to display a desired image on the display device is created by drawing the color on the color palette decided by the above-mentioned code, which pairs with each pixel, to each pixel in the target image one by one based on this image data.
By the way, in the conventional technology, a color information with only one color is assigned to each code. Therefore, when it is necessary to display different kinds of a plurality of images, it is necessary to create data for display by generating the image data of each image which is intended to display as described above, and drawing a suitable color corresponding to each pixel in the corresponding image.
Here, a creation of different image data for each target image means that an amount of necessary data becomes huge. This disadvantage especially becomes remarkable when there are a lot of target images to be displayed. Therefore, a technology, which can display a lot of images with a little amount of data by compressing the image data, is required.
An object of the present invention is to create data for display with reducing an amount of data of an image data by improving the technology concerning the data creation for display performed with a color palette.
To achieve the above-mentioned object, the following data creation device for display is proposed according to the present invention.
A data creation device for image display which generates data for image display to display a plurality of target images each having a common display range on a display device, comprises: first recording means to store a palette data which includes a plurality of color palettes and a code information, in which each of the plurality of color palettes includes a plurality of color informations, the code information includes a plurality of codes, and one of the plurality of codes specifies at least one color information of the plurality of color informations included in each of the plurality of color palettes; second memory means to store an image data including the plurality of target images, in which the image data includes a the plurality of pixels, a position information concerns to a position of each of the plurality of pixels, one of the plurality of codes corresponds to the position information, and a palette information decides which palette is used among the plurality of palettes; and drawing means to generate data for image display based on the palette data and the image data. In the above-mentioned data creation device, a number of the plurality of color palettes is the same as a number of the plurality of target images. In the above-mentioned data creation device, the drawing means allocates a color to each pixel based on the code information and the palette information corresponding to the position information on each pixel.
In the data creation device for image display according to the present invention, a plurality of color palettes, in which the number of color informations included therein is assumed to be the same, are prepared. That is, in this data creation device for image display, by associating one of color informations included in the plurality of color palettes with one code, respectively, a plurality of color informations are associated.
The advantages are as follows. If the color palette is constructed as described above, it becomes possible to make the image data of each target image common. In a word, each color palette differs from each other according to the invention, even if the image data of each target image is common, it becomes possible to display a different image.
As a result, a big compression of image data becomes possible. For example, if the image data to display four target images is assumed to be common, it becomes possible to compress the image data into a size of xc2xc. Of course, to obtain this advantage, it is necessary that a display range of each target image defined by a pixel is mutually common. However, the present invention is extremely useful as long as it satisfies this requirement.
For example, when each of a plurality of target images displays a character, it is easy to satisfy a condition that the display range defined by the pixel is mutually common for each target image, and an application of the present invention thereto is easy.
The number of codes according to the present invention can be equal to or less than the Y power of X, when the color displayed to the pixel number is X, and the number of the plurality of target images is Y. It becomes possible to correspond to all of the permutation of plurality of color informations associated with one code of like this. To correspond to all of this permutation, it is sufficient that the number of color information is set to Y power of X under the definition as mentioned-above, thereby an amount of data of the palette data can be reduced to the minimum.
In the above-mentioned data creation device, the number of the codes is 16, and the number of colors is 2 and the number of the plurality of target images is 4. When the plurality of target images displayed by two colors are displayed, it becomes possible to compress the image data into xc2xc according to this. This is suitable, for example, that the target image is an image to display a character capable of being displayed by two colors of white and black. In the above-mentioned data creation device, the number of the codes is 16, and the number of colors is 4 and the number of the plurality of target images is 2. In the above-mentioned data creation device, at least one different color is included in at least two color palettes. This means it becomes possible to compress the image data into xc2xd when the plurality of target images displayed by four colors are displayed. Both of them can be easily achieved as an application of a general-purpose 16 colors palette.
A xe2x80x98colorxe2x80x99 used in the specification includes a transparent color such as colorless transparency, translucency, and colored transparency, in addition to a color in chromatics defined by hue, brightness and color saturation.
The data creation device for image display according to the present invention as explained above can be achieved by reading a program code recorded on a record medium to a predetermined computer, for example, such as a computer device only for a game only computer device or and a home computer device.
An example of the record medium is as follows.
An article of manufacture comprising: a computer usable medium having computer readable program code means embodied therein for causing data for image display to display a plurality of target images each having a common display range on a display device to be generated, the computer readable program code means in the article of manufacture comprises: computer readable program code means for causing a computer to store a palette data which includes a plurality of color palettes and a code information, in which each of the plurality of color palettes includes a plurality of color informations, the code information includes a plurality of codes, and one of the plurality of codes specifies at least one color information of the plurality of color informations included in each of the plurality of color palettes; computer readable program code means for causing a computer to store an image data including the plurality of target images, in which the image data includes a the plurality of pixels, a position information concerns with a position of each of the plurality of pixels, one of the plurality of codes corresponds to the position information, and a palette information decides which palette is used among the plurality of palettes; and computer readable program code means for causing a computer to generate data for image display based on the palette data and the image data.
A program code according to the specification includes a concept which includes data and a control parameter, etc. necessary to display the image on the display device in addition to the program.
As is clear from the above-mentioned explanation, according to the data creation device for image display of the present invention, since the image data necessary to display the plurality of target images to be common becomes possible, it becomes possible to reduce an amount of data necessary to display the plurality of target images.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.